New hope for safe zika vaccine

GALVESTON Island researchers are among a team that has developed a vaccine that protects mice from infection by the zika virus and now they hope to prove it is safe for human use too.
Researchers from the Galveston branch of The University Of Texas Medical Branch and Brazil’s Instituto Evandro Chagas used a weakened live zika virus as the vaccine’s main ingredient.
Weakening a live virus, known as live-attenuation, reduces the severity of a disease or infection and makes it less harmful but does not eradicate it as other types of vaccination do.
Because of the significant risks of the mosquito-borne zika virus for fetuses, a vaccine is urgently needed in order to protect women of childbearing age from its effects.
As the virus can be transmitted sexually, a vaccine could also prevent infected men from passing its disease on to at-risk children.
UTMB officials said on Wednesday last week that the vaccine was created by getting rid of part of the virus’ genome, an approach already used to develop a vaccine against the dengue virus.
Pei-Yong Shi, a biochemistry and molecular biology professor at UTMB, said mice responded strongly to the vaccine, which immunized them and prevented the virus from infecting them.
Speaking about the test’s ramifications for human use, he also said the vaccine is well balanced in terms of safety and efficacy.
He said: “We chose to pursue a vaccine made from live virus that has been sufficiently attenuated, or weakened, to be safe and is able to elicit robust immune response to protect us from zika virus infection.
“Such live-attenuated vaccine has the advantage of single-dose immunization, rapid and strong immune response and potentially long-lived protection.”
Instituto Evandro Chagas director Pedro Vasconcelos, a medical virologist, agreed, saying: “Vaccines are an important tool for preventing zika virus transmission and microcephaly.
“This vaccine, the first live-attenuated vaccine for zika, will improve the public health efforts to avoid the birth defects and diseases caused by zika in countries where the virus is commonly found.”
The study’s findings were published in the Nature Medicine journal.